Archives of Gynecology and Obstetrics

, Volume 295, Issue 5, pp 1201–1209 | Cite as

The incidence of and risk factors for a repeat obstetric anal sphincter injury (OASIS) in the vaginal birth subsequent to a first episode of OASIS: a hospital-based cohort study

  • Angeliki AntonakouEmail author
  • Dimitrios Papoutsis
  • Karen Henderson
  • Zahid Qadri
  • Andrew Tapp
General Gynecology



To identify the incidence of and risk factors for a repeat obstetric anal sphincter injury (OASIS) in women who sustained an OASIS in their first vaginal delivery and have a subsequent vaginal birth.


Data were collected retrospectively for women having had singleton cephalic presentation vaginal deliveries between 2007 and 2015. Women with breech deliveries, stillbirths, foetal congenital abnormalities and multiple pregnancies were excluded.


Over the study period, we identified 11,191 women who had a first vaginal birth, of which 603 (5.4%) sustained a first episode of OASIS. Of these women, 243 (40.2%) had a subsequent pregnancy with 190 (78.1%) having a second vaginal birth, 13 (5.4%) an emergency caesarean section (CS) delivery while in labour and 40 (16.5%) an elective CS delivery. In those who delivered vaginally, 16 (8.4%) women had a repeat OASIS. After adjusting for several confounding factors, it was found that the risk of a repeat OASIS was associated with the use of epidural analgesia (OR = 3.66; 95% CI: 1.14–11.71) and an episiotomy in the first delivery (OR = 3.93; 95% CI:1. 03–15.02) and a short labour (<2.8 h) in the second delivery (OR = 14.55; 95% CI: 1.83–115.75). The time interval between the two vaginal births was not associated with any increased risk of a repeat OASIS.


We found that 8.4% of women sustained a repeat OASIS in a subsequent vaginal birth with this risk being associated with the presence of a short second labour and certain features from the first labour.


Obstetric anal sphincter injury Subsequent vaginal birth Recurrence 



We would like to thank Christopher Weston, data analyst of Medway electronic database at the Shrewsbury and Telford Hospital NHS Trust for his contribution and support in the data collection for this study.

Author contributions

AA: Protocol/project development, Data collection and data management, Data analysis, Manuscript writing and editing. DP: Protocol/project development, Data management, Data analysis, Manuscript writing and editing. KH, ZQ: Manuscript writing and editing. AT: Protocol/project development, Data analysis, Manuscript writing and editing.

Compliance with ethical standards


None. At the time of this study, Dr Angeliki Antonakou was a Postdoctoral Clinical Research Fellow in the field of perineal trauma, at the Shrewsbury and Telford Hospital, NHS Trust.

Conflict of interest

The authors declare that they have no conflict of interest.

Research involving human participants and/or animals

All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards.

Informed consent

Our study involved retrospective collection of data, and for this type of study formal consent is not required.


  1. 1.
    Hals E, Oian P, Pirhonen T, Gissler M, Hjelle S, Nilsen EB et al (2010) A multicenter interventional program to reduce the incidence of anal sphincter tears. Obstet Gynecol 116:901–908CrossRefPubMedGoogle Scholar
  2. 2.
    Hirsch E, Haney EI, Gordon TE, Silver RK (2008) Reducing high-order perineal laceration during operative vaginal delivery. Am J Obstet Gynecol 198:668CrossRefPubMedGoogle Scholar
  3. 3.
    Pollack J, Nordenstam J, Brismar S, Lopez A, Altman D, Zetterstrom J (2004) Anal incontinence after vaginal delivery: a five-year prospective cohort study. Obstet Gynecol 104:1397–1402CrossRefPubMedGoogle Scholar
  4. 4.
    Evers EC, Blomquist JL, McDermott KC, Handa VL (2012) Obstetrical anal sphincter laceration and anal incontinence 5–10 years after childbirth. Am J Obstet Gynecol 207:425.e1-6CrossRefPubMedGoogle Scholar
  5. 5.
    RCOG green-top guideline No. 29 (2015) The management of third and fourth degree perineal tears. London: RCOG Press.Google Scholar
  6. 6.
    Radestad I, Olsson A, Nissen E, Rubertsson C (2008) Tears in the vagina, perineum, sphincter ani, and rectum and first sexual intercourse after childbirth: a nationwide follow-up. Birth 35:98–106CrossRefPubMedGoogle Scholar
  7. 7.
    Roos AM, Thakar R, Sultan AH (2010) Outcome of primary repair of obstetric anal sphincter injuries (OASIS): does the grade of tear matter? Ultrasound Obstet Gynecol 36:368–374CrossRefPubMedGoogle Scholar
  8. 8.
    NICE Guideline (CG49) (2007) Faecal incontinence in adults: management.Google Scholar
  9. 9.
    Gurol-Urganci I, Cromwell DA, Edozien LC, Mahmood TA, Adams EJ, Richmond DH et al (2013) Third- and fourth-degree perineal tears among primiparous women in England between 2000 and 2012: time trends and risk factors. BJOG 120:1516–1525CrossRefPubMedGoogle Scholar
  10. 10.
    Thiagamoorthy G, Johnson A, Thakar R, Sultan AH (2014) National survey of perineal trauma and its subsequent management in the United Kingdom. Int Urogynecol J 25:1621–1627CrossRefPubMedGoogle Scholar
  11. 11.
    Edozien LC, Gurol-Urganci I, Cromwell DA, Adams EJ, Richmond DH, Mahmood TA et al (2014) Impact of third- and fourth-degree perineal tears at first birth on subsequent pregnancy outcomes: a cohort study. BJOG 121:1695–1703CrossRefPubMedGoogle Scholar
  12. 12.
    Jha S, Parker V (2016) Risk factors for recurrent obstetric anal sphincter injury (rOASI): a systematic review and meta-analysis. Int Urogynecol J 27:849–857CrossRefPubMedGoogle Scholar
  13. 13.
    Sultan AH (1999) Obstetric perineal injury and anal incontinence. Clin Risk 5:193–196Google Scholar
  14. 14.
    Koelbl H, Igawa T, Salvatore S, Laterza RM, Lowry A, Sievert KD, et al (2013) Pathophysiology of urinary incontinence, faecal incontinence and pelvic organ prolapse. In: Abrams P, Cardozo L, Khoury S, Wein A, editors. Incontinence. 5th ed. [place unknown]: ICUD-EAU; p. 261–359.Google Scholar
  15. 15.
    Cai QC, Yu ED, Xiao Y, Bai WY, Chen X, He LP et al (2012) Derivation and validation of a prediction rule for estimating advanced colorectal neoplasm risk in average-risk Chinese. Am J Epidemiol 175:584–593CrossRefPubMedGoogle Scholar
  16. 16.
    Moons KG, Harrell FE, Steyerberg EW (2002) Should scoring rules be based on odds ratios or regression coefficients? J Clin Epidemiol 55:1054–1055CrossRefPubMedGoogle Scholar
  17. 17.
    Yogev Y, Hiersch L, Maresky L, Wasserberg N, Wiznitzer A, Melamed N (2014) Third and fourth degree perineal tears–the risk of recurrence in subsequent pregnancy. J Matern Fetal Neonatal Med 27:177–181CrossRefPubMedGoogle Scholar
  18. 18.
    Lowder JL, Burrows LJ, Krohn MA, Weber AM (2007) Risk factors for primary and subsequent anal sphincter lacerations: a comparison of cohorts by parity and prior mode of delivery. Am J Obstet Gynecol 196:344.e1-5CrossRefPubMedGoogle Scholar
  19. 19.
    Scheer I, Thakar R, Sultan AH (2009) Mode of delivery after previous obstetric anal sphincter injuries (OASIS)–a reappraisal? Int Urogynecol J Pelvic Floor Dysfunct 20:1095–1101CrossRefPubMedGoogle Scholar
  20. 20.
    Harkin R, Fitzpatrick M, O’Connell PR, O’Herlihy C (2003) Anal sphincter disruption at vaginal delivery: is recurrence predictable? Eur J Obstet Gynecol Reprod Biol 109:149–152CrossRefPubMedGoogle Scholar
  21. 21.
    Baghestan E, Irgens LM, Børdahl PE, Rasmussen S (2012) Risk of recurrence and subsequent delivery after obstetric anal sphincter injuries. BJOG 119:62–69CrossRefPubMedGoogle Scholar
  22. 22.
    Jangö H, Langhoff-Roos J, Rosthøj S, Sakse A (2012) Risk factors of recurrent anal sphincter ruptures: a population-based cohort study. BJOG 119:1640–1647CrossRefPubMedGoogle Scholar
  23. 23.
    Laine K, Skjeldestad FE, Sandvik L, Staff AC (2012) Incidence of obstetric anal sphincter injuries after training to protect the perineum: cohort study. BMJ Open 17:2 (5)Google Scholar
  24. 24.
    Elvander C, Ahlberg M, Thies-Lagergren L, Cnattingius S, Stephansson O (2015) Birth position and obstetric anal sphincter injury: a population-based study of 113 000 spontaneous births. BMC Pregnancy Childbirth 15:252CrossRefPubMedPubMedCentralGoogle Scholar
  25. 25.
    Adams EJ, Bricker L, Richmond DH, Neilson JP (2001) Systematic review of third degree tears: risk factors. Int Urogynecol J Pelvic Floor Dysfunct 12(Suppl. 3):12Google Scholar
  26. 26.
    Poen AC, Felt-Bersma RJ, Strijers RL, Dekker GA, Cuesta MA, Meuwissen SG (1998) Third-degree obstetric perineal tear: long-term clinical and functional results after primary repair. Br J Surg 85:1433–1438CrossRefPubMedGoogle Scholar
  27. 27.
    Dahl C, Kjølhede P (2006) Obstetric anal sphincter rupture in older primiparous women: a case-control study. Acta Obstet Gynecol Scand 85:1252–1258CrossRefPubMedGoogle Scholar
  28. 28.
    Sheiner E, Levy A, Mazor M (2004) Precipitate labor: higher rates of maternal complications. Eur J Obstet Gynecol Reprod Biol 116:43–47CrossRefPubMedGoogle Scholar
  29. 29.
    Gottvall K, Allebeck P, Ekéus C (2007) Risk factors for anal sphincter tears: the importance of maternal position at birth. BJOG 114:1266–1272CrossRefPubMedGoogle Scholar
  30. 30.
    NICE Guideline (CG190) (2014) Intrapartum care for healthy women and babiesGoogle Scholar

Copyright information

© Springer-Verlag Berlin Heidelberg 2017

Authors and Affiliations

  • Angeliki Antonakou
    • 1
    Email author
  • Dimitrios Papoutsis
    • 1
  • Karen Henderson
    • 1
  • Zahid Qadri
    • 1
  • Andrew Tapp
    • 1
  1. 1.Department of Obstetrics and Gynaecology, Shrewsbury and Telford Hospitals NHS TrustPrincess Royal HospitalTelfordUK

Personalised recommendations